Network connectivity determination based on passive analysis of connection-oriented path information

Abstract

Passive analysis connection detection architecture that leverages connection-oriented end-to-end stack protocol information. In a TCP/IP implementation, by passively leveraging TCP information, a given system can determine in a more realtime fashion the connectivity state of a TCP pathway. Additionally, other passive information from the TCP/IP stack such as send/receive packet counts can be considered. Based on analysis of TCP path information and/or send/receive packet counts, loss of certain network connectivity can be inferred, which greatly improves the accuracy and responsiveness of detecting network connectivity losses. The disclosed architecture also facilitates improved performance when using proxy systems as means for network connectivity so as to reduce unnecessary network traffic and to route network systems to other online systems in a more efficient and effective manner.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a block diagram of a computing system that can operate in accordance with the claims.

FIG. 2 illustrates of a method for determining network connectivity.

FIG. 3 illustrates corporate Internet access using a web proxy.

FIG. 4 illustrates home Internet access using an Internet service provider.

FIG. 5 illustrates the main software components that can be used to implement the method.

FIG. 6 illustrates a method of web proxy detection and network profiling.

FIG. 7 illustrates a passive network state analyzer.

FIG. 8 illustrates an alternative implementation of a passive network state analyzer.

FIG. 9 illustrates triggered web probing via HTTP.

FIG. 10 illustrates direct web probing via HTTP.

FIG. 11 illustrates network profiling.

FIG. 12 illustrates triggered DNS probing.

FIG. 13 illustrates direct DNS probing.

FIG. 14 illustrates a computer-implemented system for determining network connectivity.

FIG. 15 illustrates a state diagram that includes selectively implemented suspect substates to state connectivity nodes.

FIG. 16 illustrates a connectivity subsystem that can be employed to provide connectivity state determination and transitioning in accordance with the innovation.

FIG. 17 illustrates a set of devices and/or systems that can employ the subsystem of FIG. 16.

FIG. 18 illustrates a server system that can employ state processing for network connectivity in accordance with the innovation.

FIG. 19 illustrates a method of determining network connectivity in accordance with the innovation.

FIG. 20 illustrates a method of transitioning to a suspect state based on connection conditions.

FIG. 21 illustrates a method of transitioning from a suspect state based on connection conditions.

FIG. 22 illustrates a method of determining connectivity state to transition from a suspect state.

FIG. 23 illustrates a method of probing for connectivity when no packets are observed during a suspect state.

FIG. 24 illustrates a schematic block diagram of an exemplary computing environment that supports connectivity determination using suspect states.

Claims

1. A computer-implemented system for determining network connectivity, comprising: a stack component for obtaining connection-oriented path information from a protocol stack, the protocol stack associated with a client; andan analysis component for computing state of the connection based on analysis of the path information.

2. The system of claim 1, wherein the connection-oriented path information is based on TCP (transmission control protocol).

3. The system of claim 1, wherein the path information represents connectivity state related to at least one of reachable, unreachable, or cannot reach.

4. The system of claim 1, wherein the analysis component further analyzes count information related to at least one of a send packet or a receive packet.

5. The system of claim 1, further comprising a state component for transitioning state of the connection between a suspect state and a connectivity state.

6. The system of claim 5, wherein the state component automatically transitions back to the connectivity state after a predetermined amount of time expires when in the suspect state.

7. The system of claim 5, wherein the analysis component initiates probing to determine the state of the connection when no packets have been observed during the suspect state.

8. The system of claim 5, wherein the state component expires the suspect state after a predetermined period of time and the suspect state has not been canceled.

9. The system of claim 1, further comprising a routing component for switching connectivity to another system based on the computed state.

10. The system of claim 1, wherein the path information of the client is related to connectivity to a proxy server.

11. The system of claim 1, further comprising a learning and reasoning component that employs a probabilistic and/or statistical-based analysis to prognose or infer an action that is desired to be automatically performed.

12. A computer-implemented method of determining network connectivity, comprising: accessing connection-oriented end-to-end path information of a protocol stack of a connection;analyzing the path information to determine a condition of the connection; andtransitioning between a connectivity state and a suspect state based the condition.

13. The method of claim 12, further comprising transitioning to the suspect state based on new unreachable path information or a new cannot reach path information.

14. The method of claim 12, further comprising transitioning to the suspect state based on an increase in packet send count with no corresponding increase in packet receive count.

15. The method of claim 12, further comprising transitioning from the suspect state based on a highest level of observed packet during the suspect state, the connectivity state associated with the highest level of the observed packet.

16. The method of claim 12, further comprising transitioning from the suspect state based on received packets that indicate an equivalent or higher connectivity level than level associated with the suspect state.

17. The method of claim 12, further comprising transitioning from the suspect state based on new reachable path information, if transition to the suspect states was based on unreachable or cannot-reach path information.

18. The method of claim 12, further comprising transitioning from an Internet connectivity state to the suspect state based only on paths to non-local remote hosts.

19. The method of claim 12, further comprising confirming the connectivity state to a proxy server of a network environment based on new reachable path information to the proxy server.

20. A computer-implemented system, comprising: computer-implemented means for accessing connection-oriented end-to-end path information of a protocol stack of a connection;computer-implemented means for analyzing the path information to determine a condition of the connection; andcomputer-implemented means for transitioning between a connectivity state and a suspect state based the condition.